A Dictionary of Neurological Signs

Utilization Behavior

U

References

Coleman RJ, Russon L, Blanshard K, Currie S. Useless hand of Oppenheim – magnetic resonance imaging findings. Postgraduate Medical Journal 1993; 69: 149-150

Oppenheim H. Discussion on the different types of multiple sclerosis. BMJ 1911; 2: 729-733

Cross References

Proprioception; Pseudoathetosis; Pseudochoreoathetosis

Utilization Behavior

Utilization behavior is a disturbed response to external stimuli, a component of the environmental dependency syndrome, in which seeing an object implies that it should be used. Two forms of utilization behavior are described:

●Induced:

when an item is given to the patient or their attention is directed to it, e.g., handing them a pair of spectacles which they put on, followed by a second pair, which are put on over the first pair.

●Incidental or Spontaneous:

when the patient uses an object in their environment without their attention being specifically directed toward it.

Another element of the environmental dependency syndrome which coexists with utilization behavior is imitation behavior (e.g., echolalia, echopraxia). Primitive reflexes and hypermetamorphosis may also be observed.

Utilization behavior is associated with lesions of the frontal lobe, affecting the inferior medial area bilaterally. It has also been reported following paramedian thalamic infarction.

References

De Renzi E, Cavalleri F, Facchini S. Imitation and utilization behavior.

Journal of Neurology, Neurosurgery and Psychiatry 1996; 61: 396-400 Lhermitte F, Pillon B, Serdaru M. Human autonomy and the frontal lobes. Part I: imitation and utilization behavior: a neuropsychological study of 75 patients. Annals of Neurology 1986; 19: 326-334

Schott JM, Rossor MN. The grasp and other primitive reflexes.

Journal of Neurology, Neurosurgery and Psychiatry 2003; 74: 558-560 Shallice T, Burgess PW, Schon F, Baxter DM. The origins of utilization behavior. Brain 1989;112: 1587-1598

Cross References

Automatic writing behavior; Echolalia; Echopraxia; Frontal lobe syndromes; Hypermetamorphosis; Imitation behavior; Primitive reflexes

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V

Valsalva Maneuver

The Valsalva maneuver is a simple test of autonomically-mediated cardiovascular reflexes, comprising forced expiration against resistance (“straining”), followed by release of the resistance and completion of expiration. The first phase produces impaired cardiac filling due to impaired venous return as a consequence of elevated intrathoracic pressure, with a fall in cardiac output and blood pressure, inducing peripheral vasoconstriction (sympathetic pathways) to maintain blood pressure. The second phase causes a transient overshoot in blood pressure as the restored cardiac output is ejected into a constricted circulation, followed by reflex slowing of heart rate.

In autonomic (sympathetic) dysfunction, reflex vasoconstriction, blood pressure overshoot and bradycardia do not occur. The latter may be conveniently assessed by measuring R-R intervals in a prolonged ECG recording, an R-R interval ratio between the straining and release phases of less than 1.1 suggesting impaired baroreceptor response.

Cross References

Orthostatic hypotension

Vegetative States

The vegetative state is a clinical syndrome in which cognitive function is lost, due to neocortical damage (hence no awareness, response, speech), while vegetative (autonomic, respiratory) function is preserved due to intact brainstem centres. Primitive postural and reflex limb movements may also be observed. The syndrome, also known as neocortical death, coma vigil, and the apallic syndrome, may be seen after extensive ischemic-hypoxic brain injury, for example following resuscitation after cardiac arrest, and needs to be distinguished from coma, akinetic mutism, and the locked-in syndrome. Persistent vegetative state (PVS) is defined by persistence of this state for > 12 months (UK) or > 6 months (USA) after brain trauma, or > 6 months (UK) or > 3 months (USA) following brain anoxia. The prognosis of PVS is poor, but occasional reports of very late recovery have appeared.

References

Jennett B. The vegetative state. Medical facts, ethical and legal dilemmas. Cambridge: CUP, 2002

Wade DT, Johnston C. The permanent vegetative state: practical guidelines on diagnosis and management. British Medical Journal 1999; 319: 841-844

Zeman A. The persistent vegetative state: conscious of nothing?

Practical Neurology 2002; 2: 214-217

Cross References

Akinetic mutism; Coma; Locked-in syndrome

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Vertigo

V

Venous Pulsation

- see RETINAL VENOUS PULSATION

Vernet’s Syndrome

- see JUGULAR FORAMEN SYNDROME

Vertigo

Vertigo is an illusion of movement, a sense of rotation or of tilt, causing a feeling of imbalance or dysequilibrium. It is a subtype of “dizziness’, to be distinguished from the light-headedness of general medical conditions (vasovagal attacks, presyncope, cardiac dysrhythmias). Vertigo is often triggered by head movement and there may be associated autonomic features (sweating, pallor, nausea, vomiting). Vertigo may be horizontal, vertical or rotatory.

Pathophysiologically, vertigo reflects an asymmetry of signaling anywhere in the central or peripheral vestibular pathways. Clinically it may be possible to draw a distinction between central and peripheral lesions: in the latter there may be concurrent hearing loss and tinnitus (reflecting vestibulocochlear (VIII) nerve involvement). Facial weakness (VII) and ipsilateral ataxia suggest a cerebellopontine angle lesion; diplopia, bulbar dysfunction and long tract signs are suggestive of a central pathology. Peripheral vertigo tends to compensate rapidly and completely with disappearance of nystagmus after a few days, whereas central lesions compensate slowly and nystagmus persists.

The clinical pattern of vertigo may gives clues as to underlying diagnosis:

Vertigo	Peripheral	Central
Acute	Labyrinthitis
Prolonged,	Otomastoiditis	Brainstem/
spontaneous	Vestibular neur(on)itis	cerebellum
	Labyrinthine concussion	hemorrhage/
	Isolated labyrinthine infarct	infarct/
	Vestibular nerve section	demyelination
	Drug-induced
Recurrent,	Ménière’s disease	Vertebrobasilar
episodic	(endolymphatic hydrops)	ischemia (with
	Autoimmune inner ear	associated
	disease (isolated, systemic)	features)
	Perilymph fistula
	Migraine (rare)
	Epilepsy (rare)
Positional	Benign paroxysmal	4th ventricle
	positional vertigo (BPPV)	lesions: multiple
		sclerosis
		Chiari
		malformation
		(contd.)

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V		Vestibulo-Ocular Reflexes
(contd.)
Vertigo	Peripheral	Central
		Brainstem/
		cerebellar tumors
		Spinocerebellar
		atrophy
Chronic	Vestibular	Neurological
	decompensation/failure	disorder
		Psychogenic

All patients with vertigo should have a Hallpike maneuver performed during the examination.

Specific treatments are available for certain of these conditions. A brief course of a vestibular sedative (cinnarizine, Serc) is appropriate in the acute phase, but exercises to “rehabilitate” the semicircular canals should be begun as soon as possible in peripheral causes. In BPPV, most patients respond to the Epley maneuver to reposition the otoconia which are thought to cause the condition (canalolithiasis). Brandt-Daroff exercises are an alternative. Cawthorne-Cooksey exercises are helpful in vestibular decompensation or failure.

References

Baloh RW. Vertigo. Lancet 1998; 352: 1841-1846

Brandt T. Vertigo: its multisensory syndromes (2nd edition). London: Springer, 1999

Hain TC, Uddin MK. Approach to the patient with dizziness and vertigo. In: Biller J (ed.). Practical neurology (2nd edition). Philadelphia: Lippincott Williams & Wilkins, 2002: 189-205

Luxon LM. Vertigo: new approaches to diagnosis and management.

British Journal of Hospital Medicine 1996; 56: 519-520, 537-541

Cross References

Ataxia; Caloric testing; Facial paresis; Hallpike maneuver, Hallpike test; Hennebert’s sign; Illusion; Nystagmus; Vestibulo-ocular reflexes

Vestibulo-Ocular Reflexes

The vestibulo-ocular reflexes (VOR) are a physiological mechanism which generates eye rotations that compensate for head movements, especially during locomotion, so stabilizing the retinal image on the fovea. VORs depend upon the integrity of the connections between the semicircular canals of the vestibular system (afferent limb of reflex arc) and oculomotor nuclei in the brainstem (efferent limb). Loss of vestibular function, as in acute bilateral vestibular failure, causes gaze instability due to loss of VORs, causing the symptom of oscillopsia (q.v.) when the head moves. As well as vestibular input, compensatory eye rotations may also be generated in response to visual information (pursuit-optokinetic eye movements) and neck proprioceptive information; anticipatory eye movements may also help stabilize the retinal image.

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Vibration V

VORs are also useful in assessing whether ophthalmoplegia results from a supranuclear or infranuclear disorder, since in the former the restriction of eye movement may be overcome, at least in the early stages, by the intact VOR (e.g., the supranuclear gaze palsy in the vertical plane in progressive supranuclear palsy).

VORs are difficult to assess in conscious patients because of concurrent pursuit-optokinetic eye movements, and because rotation of the head through large angles in conscious patients leads to interruption of VORs by vestibular nystagmus in the opposite direction (optokinetic nystagmus). The head impulse test (q.v.) may be used to test VORs in conscious patients, for example those with vertigo in whom vestibular failure is suspected. VOR may also be assessed using a slow (0.5-1.0 Hz) doll’s head maneuver while directly observing the eyes (“catch up” saccades may be seen in the absence of VOR), measuring visual acuity (dynamic visual acuity, or illegible E test; dropping two to three lines on visual acuity with head movement vs. normal if VOR impaired), and ophthalmoscopy (optic disc moves with head if VOR abnormal).

In unconscious patients, slow phase of the VORs may be tested by rotating the head and looking for contraversive conjugate eye movements (oculocephalic responses, doll’s head eye movements) or by caloric testing. VORs are lost in brainstem death.

Another important element of VOR assessment is suppression or cancellation of VOR by the pursuit system during combined head and eye tracking. VOR suppression may be tested by asking the patient to fixate on their thumbs with arms held outstretched while rotating at the trunk or sitting in a swivel chair. VOR suppression can also be assessed during caloric testing: when the nystagmus ceases with fixation, removal of the fixation point (e.g., with Frenzel’s glasses) will lead to recurrence of nystagmus in normals but not in those with reduced or absent VOR suppression. VOR suppression is impaired (presence of nystagmus even with slow head movements) in cerebellar and brainstem disease.

References

Bronstein AM. Vestibular reflexes and positional manoeuvres. Journal of Neurology, Neurosurgery and Psychiatry 2003; 74: 289-293

Leigh RJ, Brandt T. A reevaluation of the vestibulo-ocular reflex: new ideas of its purpose, properties, neural substrate, and disorders. Neurology 1993; 43: 1288-1295

Cross References

Caloric testing; Coma; Doll’s eye maneuver, Doll’s head maneuver; Hallpike maneuver, Hallpike test; Head impulse test; Ocular tilt reaction; Oculocephalic response; Oscillopsia; Supranuclear gaze palsy; Vertigo

Vibration

Vibratory sensibility (pallesthesia) represents a temporal modulation of tactile sense. On this ground, some would argue that the elevation of vibration to a “sensory modality” is not justified. Vibratory sensibility is easily tested using a tuning fork (128 Hz). This assesses the integrity of rapidly adapting mechanoreceptors (Pacinian corpuscles) and their

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V	Visual Agnosia

peripheral and central connections; the former consist of large afferent fibers, the latter of ascending projections in both the dorsal and lateral columns. The classification of both vibration and proprioception as “posterior column signs,” sharing spinal cord and brainstem pathways, is common in neurological parlance (and textbooks) but questioned by some. Instances of dissociation of vibratory sensibility and proprioception are well recognized, for instance the former is usually more impaired with intramedullary myelopathies.

Decrease in sensitivity of vibratory perception (increased perceptual threshold) is the most prominent age-related finding on sensory examination, thought to reflect distal degeneration of sensory axons.

References

Calne DB, Pallis CA. Vibratory sense: a critical review. Brain 1966; 89: 723-746

Gilman S. Joint position sense and vibration sense. Journal of Neurology, Neurosurgery and Psychiatry 2002; 73: 473-477

Cross References

Age-related signs; Myelopathy; Proprioception; Two-point discrimination

Visual Agnosia

Visual agnosia is a disorder of visual object recognition. The term derives from Freud (1891), but it was Lissauer (1890), speaking of seelenblindheit (psychic blindness), who suggested the categorization into two types which continues to be used:

●Apperceptive visual agnosia:

A defect of higher order visual perception leading to impaired shape recognition, manifested as difficulty copying shapes or matching shapes, despite preserved primary visual capacities, including visual acuity and fields (adequate to achieve recognition), brightness discrimination, color vision and motion perception (indeed motion may facilitate shape perception; see Riddoch’s phenomenon). Reading is performed with great difficulty, with a “slavish” tracing of letters which is easily derailed by any irrelevant lines; such patients may appear blind.

●Associative visual agnosia:

An impairment of visual object recognition thought not to be due to a perceptual deficit, since copying shapes of unrecognized objects is good. The scope of this impairment may vary, some patients being limited to a failure to recognize faces (prosopagnosia) or visually presented words (pure alexia, pure word blindness).

Visually agnosic patients can recognize objects presented to other sensory modalities. Clinically, apperceptive visual agnosia lies between cortical blindness and associative visual agnosia.

Apperceptive visual agnosia results from diffuse posterior brain damage; associative visual agnosia has been reported with lesions in a variety of locations, usually ventral temporal and occipital regions,

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Visual Extinction

V

usually bilateral but occasionally unilateral. Pathological causes include cerebrovascular disease, tumor, degenerative dementia (visual agnosia may on occasion be the presenting feature of Alzheimer’s disease, the so-called visual variant, or posterior cortical atrophy), and carbon monoxide poisoning.

A related syndrome which has on occasion been labeled as apperceptive visual agnosia is simultanagnosia (q.v.), particularly the dorsal variant in which there is inability to recognize more than one object at a time. Associative visual agnosia has sometimes been confused with optic aphasia (q.v.).

References

Farah MJ. Visual agnosia: disorders of object recognition and what they tell us about normal vision. Cambridge: MIT Press, 1995

Riddoch MJ, Humphreys GW. Visual agnosia. Neurologic Clinics 2003; 21: 501-520

Cross References

Agnosia; Alexia; Cortical blindness; Optic aphasia; Prosopagnosia; Riddoch’s phenomenon; Simultanagnosia; Visual form agnosia

Visual Disorientation

Visual disorientation refers to the inability to perceive more than a fragment of the visual field at any one time; it is sometimes characterized as a shifting fragment or island of clear vision. There may be difficulty fixating static visual stimuli and impaired visual pursuit eye movements.

Visual disorientation may be demonstrated by sitting directly opposite the patient and asking them, while looking at the bridge of the examiner’s nose, to reach for the examiner’s hand held up in the peripheral field of vision. Once contact is made with the hand, the examiner holds up the other hand in a different part of the field of vision. Individuals with visual disorientation will find it hard to see the hand and will grope for it, sometimes mistakenly grasping the examiner’s clothing (“tie sign”) or face.

Visual disorientation is secondary to, and an inevitable consequence of, the attentional disorder of dorsal simultanagnosia (q.v.), in which the inability to attend two separate loci leads to impaired localization. It may be a feature of Alzheimer’s disease; indeed, sometimes it may be the presenting feature, but there are usually signs of more generalized cognitive problems (e.g., impairment of episodic memory).

References

Farah MJ. Visual agnosia: disorders of object recognition and what they tell us about normal vision. Cambridge: MIT Press, 1995

Cross References

Simultanagnosia; Visual agnosia

Visual Extinction

Visual extinction is the failure to respond to a novel or meaningful visual stimulus on one side when a homologous stimulus is given simultaneously to the contralateral side (i.e., double simultaneous stimulation), despite the ability to perceive each stimulus when presented singly.

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V	Visual Field Defects

Cross References

Extinction; Neglect

Visual Field Defects

Visual fields may be mapped clinically by confrontation testing. The exact pattern of visual field loss may have localizing value due to the retinotopic arrangement of fibers in the visual pathways: any unilateral area of restricted loss implies a pre-chiasmatic lesion (choroid, retina, optic nerve), although lesions of the anterior calcarine cortex can produce a contralateral monocular temporal crescent. Bilateral homonymous scotomata are post-chiasmal in origin; bilateral heteronymous scotomata may be seen with chiasmal lesions.

Topographically, typical visual field defects are:

Retina: monocular visual loss, altitudinal field defects; central or centrocecal scotoma, ring scotoma

Optic nerve: central or centrocecal scotoma; junctional scotoma of Traquair

Optic chiasm: bitemporal hemianopia; junctional scotoma Optic tract: homonymous hemianopia, usually incongruous

Lateral geniculate nucleus: homonymous hemianopia, usually incongruous

Optic radiations: homonymous hemianopia, usually congruous; quadrantanopia

Visual cortex: homonymous hemianopia, usually congruous; quadrantanopia; cortical blindness

References

Hämäläinen HA, Julkunen LAM. Treatment of visual field defects after stroke. Advances in Clinical Neuroscience & Rehabilitation 2004;

3(6): 17-18

Schiefer U. Visual field defects: essentials for neurologists. Journal of Neurology 2003; 250: 407-411

Trobe JD, Acosta PC, Krischer JP, Trick GL. Confrontation visual field techniques in detection of anterior visual pathway lesions. Annals of Neurology 1981; 10: 28-34

Cross References

Altitudinal field defect; Hemianopia; Junctional scotoma, Junctional scotoma of traquair; Macula sparing, Macula splitting; Quadrantanopia; Scotoma

Visual Form Agnosia

This name has been given to an unusual and highly selective visual perceptual deficit, characterized by loss of the ability to identify shape and form, although color and surface detail can be appreciated, but with striking preservation of visuomotor control (i.e., a pattern of deficits inverse to those seen in optic ataxia). This reflects selective damage to the ventral (“what”) stream of visual processing in the lateral occipital area, while the dorsal (“where”) stream remains intact, yet its workings are not available to consciousness.

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Vulpian’s Sign

V

References

Goodale MA, Milner AD. Sight unseen. An exploration of conscious and unconscious vision. Oxford, OUP, 2003

Cross References

Agnosia; Optic ataxia; Visual agnosia

Visual Grasp Reflex

- see SACCADES

Visuopalpebral Reflex

- see BLINK REFLEX

Vocal Tremor, Voice Tremor

Vocal or voice tremor is a shaking, quivering, or quavering of the voice. It may be heard in:

Essential tremor

Cerebellar disorders

Spasmodic dysphonia/laryngeal dystonia

Parkinson’s disease

Motor neurone disease.

The pathophysiology is uncertain but may relate to rhythmic contractions of the cricothyroid and rectus abdominis muscles.

Cross References

Dysphonia; Tremor

Von Graefe’s Sign

Von Graefe’s sign is the retarded descent of the upper eyelid during movement of the eye from the primary position to downgaze; the lid “follows” the eye. This may be termed “lid lag,” although some authorities reserve this term for a static situation in which the lid is higher than the globe on downgaze. Von Graefe’s sign is seen in thyroid ophthalmopathy.

Cross References

Lid lag; Pseudo-von Graefe’s sign

Vorbereiden

- see GANSER PHENOMENON

VOR Suppression

- see VESTIBULO-OCULAR REFLEXES

Vulpian’s Sign

- see PREVOST’S SIGN

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W

Waddling Gait

Weakness of the proximal leg and hip girdle muscles, most often of myopathic origin, impairs the stability of the pelvis on the trunk during walking, leading to exaggerated rotation with each step, an appearance likened to the waddling of a duck. In addition, the hips may be slightly flexed and lumbar lordosis exaggerated. Neurogenic causes include spinal muscular atrophy and Guillain-Barré syndrome.

Cross References

Myopathy

“Waiter’s Tip” Posture

Lesions of the upper trunk of the brachial plexus (Erb-Duchenne type) produce weakness and sensory loss in the C5 and C6 distribution, typically with the arm hanging at the side, internally rotated at the shoulder with the elbow extended and the forearm pronated: the “waiter’s tip” posture, also sometimes known as the “porter’s tip” or “policeman’s tip.”

Cross References

Plexopathy; Radiculopathy

Wallenberg’s Syndrome

- see LATERAL MEDULLARY SYNDROME

Wall-Eyed

- see EXOTROPIA; INTERNUCLEAR OPHTHALMOGPLEGIA

Warm-Up Phenomenon

Easing of muscle stiffness with repeated contraction, the warm-up phenomenon, is reported by many patients with myotonia congenita (Thomsen’s disease, Becker’s disease), in contrast to the situation in paramyotonia.

Cross References

Myotonia; Paramyotonia

Wartenberg’s Sign

- see CORNEOMANDIBULAR REFLEX

Wartenberg’s Swing Test

Wartenberg’s swing test is used to assess limb and trunk rigidity (cf. Wartenberg’s pendulum test, used to measure spasticity, q.v.). With the patient standing, the examiner holds the shoulders and gently shakes backward and forwards, the two sides out of phase. Normally the passive arm swing induced by this movement will be out of phase with the

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